1. Field of the Invention
The invention is directed to a serial interface flash memory and more particularly, to a bias voltage generator for a reference cell adapted to a serial interface flash memory.
2. Description of Related Art
In the technical field of the related art, when performing a read operation on a serial interface flash memory, a bias voltage applying operation requiring to be performed on a gate of the reference cell would cause an effect of read disturb. The read disturb is relevant to an amount of the voltage level biased by the gate of the reference cell and the length of the bias voltage. Moreover, the read disturb causes reduction of a read margin of the serial interface flash memory, so that the performance of the serial interface flash memory is influenced.
In the technical field of the related art, the bias voltage applied to the reference cell in the serial interface flash memory is sequentially applied to a gate of the reference cell when the serial interface flash memory performs a read operation, especially an operation of reading sequential addresses. A situation where the bias voltage applying operation is received for a long term commonly leads to deterioration of the memory cell. Specially, when the serial interface flash memory is operated in a low operation frequency, a time length for the bias voltage applied to the reference cell is longer, and as a result, damages caused to the reference cell would become worse.